Yup, better to just flip a coin on which CPU to buy for your gaming rig. Makes much more sense than running a test.
I mean, I don't really know what you're getting at here. Testing a CPU at some resolution I will not use, does not help me. I will still want to know what differences there will be at my chosen resolution. Maybe there will be none at all (as in a 4k test, at least with some GPUs anyway). Or if I am a 1080p esports gamer, then maybe I'll see a big boost picking the Intel CPU.
For my part, my target is 2k @ 144 MHz, using an AMD GPU since I chose freesync. AMD does not sell a GPU that can reach those speeds (and good settings) with a single GPU solution, and may not for awhile, but at least I know what company I'll be buying from. And let's be honest, I know what CPU company I'll be buying from too, since I am a partisan when it comes to my own money. Not that I'll spend a lot of time here trying to make people think the exact same way that I do.
But for other people with the same target but no inborn loyalty to any GPU or CPU provider, if their target is (for example ) 2k@144 MHz, what are they to do with some 1080p results? Assume they'll see the same @ 2k? Let's say I have an RTX 2080 or whatever, and I am choosing between the 2700x and 8700k for the underlying CPU. At some resolution higher than 1080p, am I going to see 30% difference in fps between the two? No, probably not. I think the 8700k will show the better results. Also, if it's absolutely necessary to hit 144 MHz with some kind of settings, the 8700k is the one that's more likely to get there. Not sure if the 9900k will make it any better. More l3 is probably going to help. I do think the 2700x will put in a good showing, though. Certainly better than what we saw from these somewhat-dubious 1080p tests.
Assuming that "what I want is not a CPU test" is basically nonsense. Even @ 4k, the CPU will make some difference. As we get more and more powerful GPUs, we'll see more and more differentiation at this resolution.
The relevance of 1080p benchmarks is slipping into the past alongside 720p. I can not recommend to anyone a gaming CPU purchase based solely on 1080p results unless that is the specific resolution they plan to use every day. The results will be lopsided.